scalar

There is no equivalent operator to force an expression to
be interpolated in list context because in practice, this is never
needed. If you really wanted to do so, however, you could use
the construction @{[(someexpression)]}
, but usually a simple
(someexpression)
suffices.

Because scalar is unary operator, if you accidentally use for EXPR a
parenthesized list, this behaves as a scalar comma expression, evaluating
all but the last element in void context and returning the final element
evaluated in scalar context. This is seldom what you want.